1. Field of the Invention
The present invention relates to a machine translation system which translation is automatically performed by a computer, and especially to a machine translation system which includes an untranslated word processing function for effectively assisting the checking process for translation between many languages.
2. Description of the Related Art
The principle construction for machine translation systems under the prior art is shown by the block diagram in FIG. 1. The translation dictionary 130 in the illustrated machine translation system stores words of a same meaning corresponded for two languages, for example, English and Japanese, or French and English. Therefore, during the translation process, the translation unit 120 first divides the source language sentence (hereafter referred to as the original sentence) stored in the text storage unit 110 into separate words, and gets the syntactic structure of the sentence by using the grammar rules of the source language, before looking each of the words up in the translation dictionary 130. Next, it retrieves the words in the target language (hereafter referred to as translated words) from the translation dictionary 130 which are the equivalents of the words in the original sentence. Next, by using the syntactic structure, the retrieved translated words, and the appropriate translation grammar rules, it obtains the syntactic structure in the target language, and generates sentences in the target language by using the generation rules (hereafter referred to as the translated sentence). The generated translated sentence is then displayed alongside the original sentence on the screen of the display device 140. The user then checks the translated sentence with the original sentence displayed on the screen and then has the process move on to the translation process for the next sentence.
However, there are cases, when translating between languages, when it is unclear as to which translated word to use, or when there is no equivalent word in the target language. Since there is no entry in a column set in the translation dictionary 130 for such translated words, the reference process for the translated word will end in failure. In such a case, machine translation systems under the related art are designed so as to insert the word in the source language for which the reference process was a failure into the translated sentence which is then displayed.
FIG. 2 is a drawing showing an example of the translation displayed on the screen by a machine translation system under the related art. FIG. 2(a) shows an example of translation from Japanese to English, while FIG. 2(b) shows an example of translation from French to English. Both cases show a hypothetical example where there is no English translation for a word in the original text [the word "" in Japanese, "pain in French"]. As a result, it can be seen in FIG. 2(a) that the original Japanese word "" has been inserted. In the same way, it can be seen in FIG. 2(b) that the original French word "pain" has bean inserted. It should be noted at this point that the choice of these words has been made purely for ease of understanding of the process, since a recognized translated word, "bread", does actually exist in the English language.
However, it is not always the case that tho user will have sufficient understanding of the source language in the original sentence. If the user does not have much understanding of the source language in the original sentence, then there may be the following problem. For the example shown in FIG. 2(a), should the user not possess much understanding of the Japanese in the original sentence, then even if the untranslated word "" is displayed in Japanese to the user, then the user may not be able to understand the meaning of the untranslated word and so, as a result, may not understand the meaning of the translated sentence. In the same way, for the example shown in FIG. 2(b), should the user not possess much understanding of the French in the original sentence, then even if the untranslated word "pain" is displayed in French to the user, then the user may not be able to understand the meaning of the translated sentence.